| title | excerpt | updated |
|---|---|---|
Configuring an Additional IP |
Find out how to add Additional IP addresses to your instance's configuration |
2023-07-25 |
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Since October 6th, 2022 our service "Failover IP" is named Additional IP. This renaming has no effect on its technical features.
You may need to configure Additional IP addresses on your instances, for example if you are hosting multiple websites or international services. OVHcloud Additional IPs allow you to associate multiple IP addresses with a single network interface.
This guide explains how to add Additional IP addresses to your network configuration.
Warning
OVHcloud is providing you with services for which you are responsible, with regard to their configuration and management. You are therefore responsible for ensuring they function correctly.
This guide is designed to assist you in common tasks as much as possible. Nevertheless, we recommend that you contact a specialist service provider if you have difficulties or doubts concerning the administration, usage or implementation of services on a server.
- A Public Cloud instance in your OVHcloud account
- An Additional IP address or an Additional IP block
- Administrative access (sudo) via SSH or GUI to your instance
- Basic networking and administration knowledge
The following sections contain the configurations for the most commonly used distributions/operating systems. The first step is always to log in to your instance via SSH or a GUI login session (VNC for a Windows instance). The examples below presume you are logged in as a user with elevated permissions (Administrator/sudo).
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Concerning different distribution releases, please note that the proper procedure to configure your network interface as well as the file names may have been subject to change. We recommend to consult the manuals and knowledge resources of the respective OS versions if you experience any issues.
Please take note of the following terminology that will be used in code examples and instructions of the guide sections below:
| Term | Description | Examples |
|---|---|---|
| ADDITIONAL_IP | An Additional IP address assigned to your service | 169.254.10.254 |
| NETWORK_INTERFACE | The name of the network interface | eth0, ens3 |
| ID | ID of the IP alias, starting with 0 (depending on the number of additional IPs there are to configure) | 0, 1 |
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When configuring an Additional IP on a Public Cloud instance, you do not need a gateway and subnet mask.
Open the following file path with a text editor:
sudo nano /etc/cloud/cloud.cfg.d/99-disable-network-config.cfgEnter the following line, then save and exit the editor.
network: {config: disabled}Creating this configuration file will prevent changes to your network configuration from being made automatically.
You can verify your network interface name with this command:
ip aOpen the network configuration file for editing with the following command:
sudo nano /etc/network/interfaces.d/50-cloud-initThen add the following lines:
auto NETWORK_INTERFACE:ID
iface NETWORK_INTERFACE:ID inet static
address ADDITIONAL_IP
netmask 255.255.255.255Apply the changes with the following command:
sudo systemctl restart networkingThe configuration file for your Additional IP addresses is located in /etc/netplan/. In this example it is called "50-cloud-init.yaml". Before making changes, verify the actual file name in this folder. Each Additional IP address will need its own line within the file.
Open the following file path with a text editor:
sudo nano /etc/cloud/cloud.cfg.d/99-disable-network-config.cfgEnter the following line, then save and exit the editor.
network: {config: disabled}Creating this configuration file will prevent changes to your network configuration from being made automatically.
You can verify your network interface name with this command:
ip aOpen the network configuration file for editing with the following command:
sudo nano /etc/netplan/50-cloud-init.yamlDo not change the existing lines in the file; add your Additional IP address according to the example below:
network:
version: 2
ethernets:
NETWORK_INTERFACE:
dhcp4: true
match:
macaddress: fa:xx:xx:xx:xx:63
set-name: NETWORK_INTERFACE
addresses:
- ADDITIONAL_IP/32Warning
It is important to respect the alignment of each element in this file as represented in the example above. Do not use the tab key to create your spacing.
Save and close the file.
You can test your configuration using this command:
sudo netplan tryIf it is correct, apply it using the following command:
sudo netplan applyRepeat this procedure for each Additional IP address.
Log in to the OVHcloud Control Panel, go to the Public Cloud{.action} section, and select the Public Cloud project concerned.
Open Instances{.action} in the left-hand menu and click on the name of your instance. Switch to the tab VNC console{.action}.
Right-click on the Start Menu{.action} button and open Run{.action}.
Type cmd and click OK{.action} to open the command line application.
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In order to retrieve the current IP configuration, enter ipconfig at the command prompt.
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Now you need to change the IP properties to a static configuration.
Open the adapter settings in the Windows control panel and then open the Properties{.action} of Internet Protocol Version 4 (TCP/IPv4){.action}.
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In the IPv4 Properties window, select Use the following IP address{.action}. Enter the IP address which you have retrieved in the first step, then click on Advanced{.action}.
In the new window, click on Add...{.action} under "IP addresses". Enter your Additional IP address and the subnet mask (255.255.255.255).
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Confirm by clicking on Add{.action}.
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Back in the control panel (Network Connections{.action}), right-click on your network interface and then select Disable{.action}.
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To restart it, right-click on it again and then select Enable{.action}.
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Open the command prompt (cmd) and enter ipconfig. The configuration should now include the new Additional IP address.
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You can verify your network interface name with this command:
ip aOpen the network configuration file for editing:
sudo nano /etc/sysconfig/network-scripts/ifcfg-NETWORK_INTERFACE:IDThen add these lines:
DEVICE=NETWORK_INTERFACE:ID
BOOTPROTO=static
IPADDR=ADDITIONAL_IP
NETMASK=255.255.255.255
BROADCAST=ADDITIONAL_IP
ONBOOT=yesApply the changes with the following command:
sudo systemctl restart networkingIn the Plesk control panel, choose Tools & Settings{.action} from the left-hand sidebar.
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Click on IP Addresses{.action} under Tools & Resources.
In this section, click on the button Add IP Address{.action}.
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Enter your Additional IP in the form xxx.xxx.xxx.xxx/32 into the field "IP address and subnet mask", then click on OK{.action}.
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Back in the section "IP Addresses", verify that the Additional IP address was added correctly.
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First, soft-reboot your instance via the instance's OS or from the OVHcloud Control Panel. If you are still unable to establish a connection from the public network to your Additional IP and suspect a network problem, you need to reboot the instance in rescue mode. Then you can set up the Additional IP address directly on the instance.
Once you are connected in rescue mode via SSH, enter the following command:
ifconfig ens3:0 ADDITIONAL_IP netmask 255.255.255.255 broadcast ADDITIONAL_IP upTo test the connection, simply ping your Additional IP from the outside. If it responds in rescue mode, that probably means that there is a configuration error. If, however, the IP is still not working, please inform our support teams by creating a support request in your OVHcloud Control Panel for further investigations.
If you need training or technical assistance to implement our solutions, contact your sales representative or click on this link to get a quote and ask our Professional Services experts for assisting you on your specific use case of your project.
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